We are currently in the midst of a genetics revolution that promises to push "breakthrough" biomedical research to new levels. A large part of this revolution depends upon the analysis of the relationships between genes and their effects on complex biological systems and phenotypes. Investigators must become increasingly skilled in the manipulation and use of genetic models to address a variety of important biological questions. The recent decision by President Bush to allow National Institutes of Health funding of human embryonic stem (ES) cell research creates a tremendous opportunity for U.S. investigators. The current major bottleneck to human ES cells becoming a ubiquitous research tool in the biomedical research community is the hands-on training necessary to learn how to culture these sensitive cells. The course proposed in this application, "Current Protocols in Stem Cell Biology", will provide hands-on training for investigators to learn how to culture, manipulate, and differentiate ES cells from human, mouse and zebrafish in vitro. This course will bring together some of the leading experts on ES cell technology and through comparative approaches, effectively train students in the successful culture, maintenance and manipulation of ES cells. A major long term goal for this course will be to share and improve standard protocols, and eventually to publish a technique manual, similar in style to the popular "Manipulating the Mouse Embryo" manual edited by Hogan et al. Specifically, this course will cover: 1) The preparation of media, including necessary quality control; 2) The preparation of feeder layers; 3) ES cell passaging techniques; 4) ES cell cryopreservation; 5) ES cell transfection techniques; 6) FACs analysis of ES cells and their differentiated derivatives; 7) Embryoid body formation; 8) Neural Differentiation of ES cells; 9) Hematopoietic Differentiation of ES cells; and 10) Cardiac Differentiation of ES cells. These aims will be accomplished by offering an intensive 5-day course to 16 participants chosen for their outstanding research potential. The Course will be held on August 5-9, 2002 at The Jackson Laboratory in Bar Harbor, Maine, and will be followed by a companion symposium "Stem Cells on Land and at Sea" to be held at The Mount Desert Island Biological Laboratory on August 9-12.